Ways to improve the reproducibility of cell viability measurements with the MTT assay

Abstract

In recent years, methodological aspects of in vitro studies of nanoparticle toxicity have been actively discussed, including a possibility to improve the reproducibility of cell viability measurements. Such measurements are known as the most common cytotoxicity test both for nanoparticles and for other biologically important materials. Earlier we suggested a novel method for determining contributions of various aerosol-OT (AOT) forms to the cytotoxicity of aqueous silver nanoparticle (AgNP) solutions. This method provides a sufficiently high reproducibility of cell viability values to obtain reliable quantitative estimates of differences in average viability values. To solve this task, details of the procedure were modified from respective steps of the procedure commonly used in this area of nanomedicine. As a result, it became possible to obtain a qualitatively new information about the mechanism of action on cells of both surfactants and surfactant-stabilized nanoparticles. In the present work using the action of an aqueous AOT solution on endothelial cells as an example, we described the procedure-improving changes that allowed us to reduce significantly standard deviations from mean values of cell viability. Such changes are not specific for experiments neither with AOT-stabilized AgNPs solutions nor with endothelial cells but may be useful for cytotoxicity studies of solutions of biologically active agents (including metal nanoparticles) on various cell types.